The present invention relates to a thermal transfer recording medium.
Heretofore, various kinds of thermal transfer recording media have been used in a variety of printing apparatuses. However, in the case of thermal transfer recording media for bar code printing, label printing and rough paper printing wherein the main object of printing is papers having a poor surface smoothness, and a thermal transfer recording medium of correctable type which gives correctable print images, among the above-mentioned thermal transfer recording media, the problem that print images are insufficient in durability such as scratch resistance or abrasion resistance is encountered.
For instance, when a printed matter obtained by using these conventional recording media is passed through a facsimile machine, the print image is rubbed with a sliding member provided inside the machine, so that the print image, in some cases, is peeled partially or scratches occur in the print image. In the case of a printed matter obtained by printing on a rough paper having a Bekk smoothness of about 20 seconds, the print image, in some cases, becomes unclear merely by rubbing the surface of the printed matter with the finger, etc. In the case of a printed matter obtained by using the conventional correctable recording medium, even the image printed on a smooth paper is not necessarily sufficient in scratch or abrasion resistance. Further, a printed matter obtained by using the conventional recording medium for bar code printing does not necessarily satisfy the essential requirement for bar code that even though the image surface is rubbed a little, the image is not damaged and can be accurately read.
Various attempts were made to improve the durability of print image. However, when the durability of print image is improved, there occur the problem that the selective transferability of the ink layer becomes poor so that the quality of the obtained image is poor, and another problem that the quality of correction of erroneous print image, which means the appearance quality of the trace of the erroneous print image removed from the receiving paper, is poor. Herein, the term "selective transferability" means that only the portion of the ink layer heated with a heating element is sharply separated from the remaining portions of the ink layer and transferred to a receiving paper to give an ink dot having substantially the same shape as that of the heating element. Thus, there has not been obtained any thermal transfer recording medium satisfying both the durability and the quality of print image.
An object of the present invention is to provide a thermal transfer recording medium capable of giving print images having an excellent durability without any deterioration in the quality of the print images and the quality of correction.
This and other objects of the invention will become apparent from the description hereinafter.